Boston Marathon Bombing

Suspect #2 Remains

in Serious Condition

4/20/2013 5:10 AM PDT BY TMZ STAFF

Dzhokhar Tsarnaev -- the 19-year-old suspect in the Boston Marathon bombing -- remains in serious condition at Beth Israel Deaconess Hospital in Boston following his capture last night in Watertown, MA.

Tsarnaev was found hiding inside a boat that sat in the driveway of David Henneberry, who became suspicious when he saw the boat's tarp flapping in the wind. Henneberry's stepson told CNN he went out to investigate when he noticed the tarp had been cut ... and a closer inspection revealed it was stained with blood.

Henneberry investigated further and, according to his stepson, "He basically stuck his head under the tarp (and) noticed a pool of blood."

Upon his capture, Tsarnaev was not read his Miranda rights because the authorities instead invoked the public safety exception to question him extensively about other potential explosive devices or accomplices and to try to gain intelligence.

Tsarnaev's older brother, Tamerlan, died following a gunfight with police early Friday morning.